I have been seeing this problem too, but only on canvas. You can see an example of this if you look at the Space Shooter dev app at http://www.m2ag.net/dev/shooter/ with a canvas browser (ie i guess). Just enter the game and select the dev game on the first menu. Click the glowing bar at the bottom and shoot the (white) ice. Shooting ice one after the other will show the flashes. It shows up really well on ipad, but the current version of my game is afu on the ipad right now.
I tried blaming it on Construct2's canvas renderer, but it turns out I was doing it wrong.
The ice_explosion sprite is a one shot shared between all the ice sizes. To clear the flashing up I destroy the ice explosion object before the one shot particle timeout.
In this case I set the Particle life time Timeout to 2.1, and in my event triggering the explosion I wait 2.0 seconds before the end and destroy the object.